Stephen Coco, a detective sergeant who was working in the Special Investigations Unit in Manchester, turned himself in to police Tuesday, four days after two teenage boys were hit from behind as they were walking along a street. The vehicle left without stopping.

Authorities wouldn't confirm whether the 41-year-old Coco was driving. He was arraigned on two felony counts of conduct after an accident and was released on $20,000 personal recognizance bail.

The boys, ages 17 and 18, were hospitalized but are now at home recovering.

Manchester police fired Coco, a 17-year veteran of the department, on Monday. They said he had violated departmental standard operating procedures.